How to configure priorityclass for job

Background

When a user creates a job, if there is no PriorityClassName specified in the template of the task, the task will use the PriorityClassName specified by the job. The user can specify PriorityClassName in each task’s template to override the configuration of job, so that priority can be configured separately for each task.

Key Points

• If the task does not specify PriorityClassName but the job does, the task will use the job’s PriorityClass, and the PreemptionPolicy and priority value will also be the same as the job.
• When user needs to allow task in job to preempt other tasks if the resources are insufficient, a separate PriorityClassName must be set in the task’s template, and it is important to note that if there are multiple tasks that need to be set to different priorities, then user need to set the PriorityClassName for all of them, otherwise the task that does not specify PriorityClassName will use the PriorityClass of the job it belongs to.

Example

apiVersion: scheduling.k8s.io/v1
kind: PriorityClass
metadata:
  name: job-priority
value: 1
preemptionPolicy: Never
---
apiVersion: scheduling.k8s.io/v1
kind: PriorityClass
metadata:
  name: task-priority
value: 10
---
apiVersion: batch.volcano.sh/v1alpha1
kind: Job
metadata:
  name: job
spec:
  schedulerName: volcano
  priorityClassName: job-priority
  minAvailable: 1
  tasks:
    - replicas: 1
      name: preempt-task
      template:
        spec:
          priorityClassName: task-priority # The priorityclass is specified individually for this task
          containers:
            - image: alpine
              command: ["/bin/sh", "-c", "sleep 1000"]
              name: preempt
              resources:
                requests:
                  cpu: 1
    - replicas: 1
      name: non-preempt-task # This task does not specify PriorityClassName, so it will use the "job-priority" priorityclass specified by job
      template:
        spec:
          containers:
            - image: alpine
              command: ["/bin/sh", "-c", "sleep 1000"]
              name: non-preempt
              resources:
                requests:
                  cpu: 1